DB Autogyro

[Thomas W Shelley]

I apologise if this model is already mentioned somewhere on the forum but I couldn't find anything in any detail. 

 

I just picked up a secondhand David boddington Autogyro and one thing that perplexes me is that the blades are just flat pieces of balsa. No airfoil and not even a leading edge - looking at other photos it seems like this is the way it was intended. 

 

1. How does it create lift without an airfoil? With the negative incidence on each blade I can see them spinning up easily but in terms of lift I'm starting to think I haven't quite grasped how gyros work. 

 

2. If I took off the covering and sanded them into an airfoil - would it make much difference? 

 

[Paul De Tourtoulon]

I have a rotorutter twin autogyro and the blades are also flat planks of balsa and it flies well.

[Stephen Jones]

A paper aeroplane has no aerofoil yet it flies ok.

Most foamboard plane also do not have a aerofoil. 

 

So yes a flat surface can generate lift , however it is not very efficient.

If the airspeed is too slow will not work and if too fast also will not work.

Autogyros tend to only go slow so is ok.

 

So do not sand those blades they will be fine.

Steve.

[Nick Cripps]

I saw one fly at the Cranfield show many years ago. One of the rotors was stuck and didn't rotate - made no difference whatsoever!

[Kevin Fairgrieve]

My Kestral Autogyro (Free RCM&E plan build) also has flat plate blade`s.

 

Fly`s fine.